U.S. patent number 10,595,888 [Application Number 14/882,322] was granted by the patent office on 2020-03-24 for self-closing devices and apparatus and methods for making and delivering them.
This patent grant is currently assigned to SOLINAS MEDICAL INC.. The grantee listed for this patent is Solinas Medical Inc.. Invention is credited to James Hong, Amy Lee, Erik van der Burg.
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United States Patent |
10,595,888 |
Hong , et al. |
March 24, 2020 |
Self-closing devices and apparatus and methods for making and
delivering them
Abstract
A self-closing device for implantation within a patient's body
includes base material including an inner surface area for securing
the base material to a tissue structure, and a plurality of support
elements surrounding or embedded in the base material. The support
elements are separable to accommodate creating an opening through
the base material for receiving one or more instruments through the
base material, and biased to return towards a relaxed state for
self-closing the opening after removing the one or more
instruments. The device may be provided as a patch, cuff, or
integrally attached to a tubular graft or in various shapes.
Inventors: |
Hong; James (Sunnyvale, CA),
Lee; Amy (Sunnyvale, CA), van der Burg; Erik (Los Gatos,
CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Solinas Medical Inc. |
Santa Clara |
CA |
US |
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Assignee: |
SOLINAS MEDICAL INC. (Santa
Clara, CA)
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Family
ID: |
51690053 |
Appl.
No.: |
14/882,322 |
Filed: |
October 13, 2015 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20160199085 A1 |
Jul 14, 2016 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/US2014/033892 |
Apr 12, 2014 |
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61811733 |
Apr 13, 2013 |
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61811719 |
Apr 13, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F
2/92 (20130101); A61F 2/95 (20130101); A61M
39/02 (20130101); A61B 17/0057 (20130101); A61B
17/32 (20130101); A61F 2/962 (20130101); A61F
2/89 (20130101); A61F 2/07 (20130101); A61B
2017/0061 (20130101); A61F 2002/075 (20130101); A61B
2017/00659 (20130101); A61B 2017/00526 (20130101); A61B
2017/00867 (20130101); A61B 2017/00676 (20130101); A61B
2017/320044 (20130101); A61B 2017/00623 (20130101) |
Current International
Class: |
A61F
2/92 (20130101); A61B 17/00 (20060101); A61F
2/95 (20130101); A61B 17/32 (20060101); A61F
2/89 (20130101); A61F 2/962 (20130101); A61F
2/07 (20130101); A61M 39/02 (20060101); A61F
17/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101384228 |
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Mar 2009 |
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CN |
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1649888 |
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Apr 2006 |
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EP |
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9846115 |
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Oct 1998 |
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WO |
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2007061787 |
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May 2007 |
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WO |
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2010015001 |
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Feb 2010 |
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WO |
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2011112755 |
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Sep 2011 |
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WO |
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WO-2011112755 |
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Sep 2011 |
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WO |
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Other References
Korean Intellectual Property Office, International Search Report
for corresponding International Application No. PCT/US2014/033892,
Applicant: Solinas Medical, Inc., Form PCT/ISA/210, dated Aug. 28,
2014, 4 pages. cited by applicant .
Korean Intellectual Property Office, International Preliminary
Report on Patentability for corresponding International Application
No. PCT/US2014/033892, Applicant: Solinas Medical, Inc.,Forms
PCT/IB/373 and PCT/ISA/237 dated Aug. 27, 2014, 14 pages. cited by
applicant .
Kita-Aoyama International Patent Bureau, Office Action and
translation from corresponding Japanese application No.
2016-507697, Applicant: Solinas Medical, Inc., dated Mar. 13, 2018,
6 pages. cited by applicant .
Assion, Jean-Charles, European Patent Office Examination Report for
Corresponding European Patent Application No. 14783249.7-1122,
dated Jun. 17, 2019, 4 pages. cited by applicant.
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Primary Examiner: Cigna; Jacob J
Attorney, Agent or Firm: English; William A. Vista IP Law
Group LLP
Government Interests
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND
DEVELOPMENT
This invention was made with Government support under SBIR Grant
Nos. 1143198 and 1329172 awarded by the National Science
Foundation. The Government has certain rights in the invention.
Parent Case Text
RELATED APPLICATION DATA
This application is a continuation of co-pending International
Application No. PCT/US2014/033892, filed Apr. 12, 2014, which
claims benefit of U.S. provisional application Ser. Nos. 61/811,719
and 61/811,733, both filed Apr. 13, 2013. This application is also
related to U.S. application Ser. No. 13/607,783, filed Sep. 9,
2013, International Application No. PCT/US2011/027726, filed Mar.
9, 2012, and provisional application Ser. Nos. 61/312,183, filed
Mar. 9, 2010, and 61/385,483, filed Sep. 22, 2010. The entire
disclosures of these applications are expressly incorporated by
reference herein.
Claims
We claim:
1. A method for making an access device, comprising: creating a
plurality of zigzag bands disposed adjacent one another and one or
more flexible connectors extending between adjacent zigzag bands,
the flexible connectors biased to an original curvilinear shape
aligned along a longitudinal axis; elastically lengthening and at
least partially straightening the curvilinear shape the flexible
connectors along the longitudinal axis to a stressed state, thereby
increasing spacing between the adjacent zigzag bands; embedding the
zigzag bands within a base material with the flexible connectors in
the stressed state; and releasing the zigzag bands whereupon the
flexible connectors are biased to return towards original the
curvilinear shape, thereby pre-stressing the base material in a
longitudinal direction along the longitudinal axis.
2. A method for making an access device, comprising: creating a
plurality of elongate zigzag members, each zigzag member defining a
longitudinal axis extending between opposite ends thereof, each
zigzag member comprising a plurality of zigzag elements lying
within a plane and extending between the opposite ends along the
longitudinal axis in an original curvilinear shape; elastically
lengthening the zigzag members along the longitudinal axis to at
least partially straighten the zigzag elements to a stressed state;
embedding the zigzag members within a base material in the stressed
state; and releasing the zigzag members whereupon the zigzag
elements are biased to return towards the original curvilinear
shape, thereby pre-stressing the base material in a longitudinal
direction along the longitudinal axis.
3. The method of claim 2, wherein the zigzag members are created in
a cylindrical shape defining a relaxed diameter such that the
zigzag members lie within a curved plane extending around a
circumference of the cylindrical shape, the method further
comprising: mounting the zigzag members within a cavity of a mold;
elastically expanding the zigzag members from the relaxed diameter
to an expanded diameter; injecting base material into the cavity to
encase the zigzag members therein, wherein the zigzag members are
mounted within the cavity in the expanded diameter when the base
material is injected into the cavity; and releasing the zigzag
members from the expanded diameter whereupon the zigzag members are
biased towards the relaxed diameter to pre-stress the base
material.
4. The method of claim 2, wherein the zigzag members are created in
a planar shape, and wherein embedding the zigzag members within a
base material comprises: placing the zigzag members within a cavity
of a receptacle; applying material within the cavity to encase the
zigzag members therein and excess base material is disposed over
the zigzag members and extends out of the cavity; and removing the
excess material.
5. The method of claim 2, wherein, upon releasing, the zigzag
members impose a substantially continuous compressive force on the
adjacent base material along the longitudinal axis to enhance
sealing any passages created through the base material.
6. The method of claim 2, wherein the access device has a generally
"C" shaped cross-section including longitudinal edges extending
parallel to the longitudinal axis.
7. The method of claim 2, wherein embedding the zigzag members
comprises: mounting the zigzag members within a cavity of a mold;
and injecting base material into the cavity to encase the zigzag
members therein.
8. The method of claim 7, wherein the zigzag members are created in
a planar shape lying within the plane defining a relaxed
configuration, the method further comprising: elastically expanding
the zigzag members within the plane from the relaxed configuration
to an expanded configuration defining the stressed state, and
wherein the zigzag members are mounted within the cavity in the
expanded configuration when the base material is injected into the
cavity; and releasing the zigzag members from the expanded
configuration whereupon the zigzag members are biased towards the
relaxed configuration to pre-stress the base material.
9. The method of claim 2, wherein the zigzag members are created in
a planar shape, and wherein embedding the zigzag members within the
base material comprises: applying base material in a liquid or
uncured viscous state within a receptacle; placing the zigzag
members such that the zigzag members are on or in the base material
within the receptacle; and curing the base material to embed the
zigzag members therein.
10. The method of claim 9, further comprising removing excess base
material from the receptacle before placing the zigzag members on
or in the base material.
11. A method for making an access device, comprising: creating a
plurality of elongate zigzag members defining a longitudinal axis,
each zigzag member comprising a plurality of zigzag elements lying
within a plane and extending along the longitudinal axis in an
original curvilinear shape; elastically lengthening the zigzag
members to at least partially straighten the zigzag elements to a
stressed state; embedding the zigzag members within a base material
in the stressed state; and releasing the zigzag members whereupon
the zigzag elements are biased to return towards the original
curvilinear shape, thereby pre-stressing the base material in a
longitudinal direction, wherein the zigzag members are created in a
planar shape, and wherein embedding the zigzag members within a
base material comprises: creating a planar first layer of base
material; inserting the zigzag members into a surface of the first
layer; rolling the first layer and zigzag members around a mandrel;
and applying a second layer of base material around the zigzag
members and first layer around the mandrel.
12. A method for making an access device, comprising: creating a
plurality of elongate zigzag members defining a longitudinal axis,
each zigzag member comprising a plurality of zigzag elements lying
within a plane and extending along the longitudinal axis in an
original curvilinear shape; elastically lengthening the zigzag
members to at least partially straighten the zigzag elements to a
stressed state; embedding the zigzag members within a base material
in the stressed state; and releasing the zigzag members whereupon
the zigzag elements are biased to return towards the original
curvilinear shape, thereby pre-stressing the base material in a
longitudinal direction, wherein the zigzag members are created in a
planar shape, and wherein embedding the zigzag members within a
base material comprises: creating a planar first layer of base
material over a die stamp including a pattern corresponding to the
shape of the zigzag members; removing the die stamp to expose the
pattern of features corresponding to the pattern on the die stamp;
placing the zigzag members on the first layer such that the zigzag
members are engaged with the features; and applying a second layer
of base material over the zigzag members and first layer.
13. The method of claim 12, wherein the features are recesses in an
exposed surface of the base layer, and wherein placing the zigzag
members on the first layer comprises placing the zigzag members
such that the zigzag members are received within the recesses.
14. The method of claim 12, wherein the features extend outwardly
from the first surface, and wherein placing the zigzag members on
the first layer comprises placing the zigzag members at least
partially around the features.
Description
FIELD OF THE INVENTION
The field of the invention generally relates to self-closing
devices that are implantable within a patient's body and to
apparatus, systems, and methods including such self-closing
devices. For example, the present invention may include
self-closing tubular structures, cuffs, or patches, and/or grafts
that include resealable access ports or regions including
self-closing tubular structures, and/or may include systems and
methods for making and implanting such self-closing structures
and/or grafts.
BACKGROUND
Dialysis for end stage renal disease ("ESRD") is one of the leading
and rapidly growing problems facing the world today. In 2006, there
were greater than fifty one million (51,000,000) people in the
United States diagnosed with chronic kidney disease. Greater than
five hundred thousand (500,000) people in this population suffered
from ESRD. With the growing aging population and increasing
prevalence of high risk factors such as diabetes (35% of all ESRD
patients, Szycher M., J Biomater Appl. 1999; 13, 297-350) and
hypertension (30%), the projected population in 2020 is greater
than seven hundred eighty four thousand (784,000) (est. USRDS
2008).
The two primary modes of treatment are kidney transplant and
hemodialysis. Due to the shortage of available transplant kidneys,
approximately seventy percent (70%) of people with ESRD undergo
hemodialysis (USRDS 2008) for life or until a transplant kidney
becomes available. To facilitate the frequent, periodic treatments,
patients must undergo vascular surgery to prepare their artery and
vein, typically in their forearms, for dialysis. The two most
common methods of preparing the artery and vein are arteriovenous
(AV) fistulas and AV grafts--the former is the preferred option due
to longer patency rates; however fistulas are often replaced by AV
grafts once the life of the fistula has been exhausted.
There are advantages and disadvantages to both methods. Most
notably, grafts are easy to implant, and ready to use relatively
sooner, but have shorter lifespans and are more prone to infection
and thrombus formation. Fistulas have greater durability and are
less prone to infection, but can take up to six (6) months (KDOQI)
to mature before use, and the veins used for access have tendencies
to develop pseudo-aneurysms at the site of repeated access. One of
the contributing factors to the rapid degradation of current AV
grafts and/or veins is the repeated needle sticks during dialysis
with relatively large needles (e.g., 14-16 Gauge). This is
exacerbated because the average patient undergoes hemodialysis
treatment two or three times a week, every week of every year until
a kidney replacement is available or until the end of their life
expectancy, which is approximately ten (10) years (Szycher M., J
Biomater Appl. 1999; 13, 297-350). Moreover, due to the high risk
of intimal hyperplasia and vessel narrowing, dialysis patients also
undergo periodic interventional treatment to maintain patent
vessels, which may occur several times a year. This typically
involves angioplasty or stenting, akin to the treatment of coronary
vascular occlusions, and vascular access using needles is also
needed for these procedures, thereby contributing to the risk of
graft or vessel degradation.
Therefore, there is an apparent need for devices, systems, and
methods for treating ESRD and other conditions.
SUMMARY
The present application generally relates to self-closing devices
that are implantable within a patient's body and to apparatus,
systems, and methods including such self-closing devices. For
example, apparatus, systems, and methods described herein may
include self-closing tubular structures, cuffs, or patches, and/or
grafts that include resealable access ports or regions including
self-closing structures. In addition, systems and methods for
making and using such devices are also provided.
In accordance an exemplary embodiment, a self-sealing access device
is provided that includes base material, e.g., elastomeric and/or
bioabsorbable material, including a surface area for securing the
base material to a tissue structure; and a plurality of elastic
support elements surrounding or embedded in the base material. The
support elements may be separable to accommodate creating an
opening through the base material for receiving one or more
instruments through the base material, and biased to return towards
a relaxed state for self-closing the opening after removing the one
or more instruments. In exemplary embodiments, the device may be a
cuff, a patch, or other device that may be secured around or to a
tubular, curved, or substantially flat body structure.
For example, the support elements may include a plurality of struts
spaced apart from one another to define openings in a relaxed or
relatively low stress state. The struts may be separable from one
another, e.g., to a relatively high stress state, to accommodate
receiving one or more instruments through the openings and the base
material filling or adjacent to the openings, the struts
resiliently biased to return towards one another, e.g., to the
relaxed or relatively low stress state.
In accordance with still another embodiment, a method is provided
for implanting an access device into a patient's body that includes
exposing a tubular body or other surface within a patient's body,
e.g., a curved or substantially flat surface of a tubular body or
other tissue structure, such as a vessel or graft, a heart, or a
wall of the abdomen; and attaching an access device to the outer
surface of the tubular body or tissue structure. The access device
may include base material and a plurality of elastic support
elements, the support elements separable to accommodate creating an
opening through the base material for receiving one or more
instruments through the base material, and biased to return towards
a relaxed or relatively low stress state for self-closing the
opening after removing the one or more instruments.
In accordance with yet another embodiment, a system is provided for
accessing a tissue structure or graft implanted within a patient's
body that includes a self-closing access device and an apparatus
for introducing the access device into a patient's body. For
example, the access device may include a cuff or patch that may be
attached to the tissue structure or graft, e.g., including base
material, e.g., elastomeric and/or bioabsorbable material, and a
plurality of elastic support elements surrounding or embedded in
the base material. The apparatus may include a dissector, e.g.,
having a blunt dissecting edge, carrying the access device, and a
constraint for releasably securing the access device to the
dissector. In an exemplary embodiment, the dissector may have a
generally "C" shaped cross-section, e.g., defining a longitudinal
slot, allowing the dissector and the access device thereon to be
advanced over and/or around a blood vessel or other body
structure.
In accordance with another embodiment, a method is provided for
making an access device that includes wrapping a strand
circumferentially around a mandrel in a zigzag pattern to define a
first annular ring; offsetting the strand and wrapping the strand
around the mandrel in a zigzag pattern to define a second annular
ring adjacent the first annular ring; removing the strand from the
mandrel; separating the first and second annular rings from one
another resulting in free ends on each of the first and second
annular rings; attaching the free ends together to define first and
second enclosed annular rings; and embedding the first and second
enclosed annular rings within a flexible base material.
In accordance with still another embodiment, a method is provided
for making an access device that includes creating a plurality of
zigzag bands disposed adjacent one another and one or more flexible
connectors extending between adjacent zigzag bands, the flexible
connectors biased to an original curved shape; elastically
lengthening and at least partially straightening the flexible
connectors to a stressed state, thereby increasing spacing between
the adjacent zigzag bands; embedding the zigzag bands within a base
material with the flexible connectors in the stressed state; and
releasing the zigzag bands whereupon the flexible connectors are
biased to return towards original the curved shape, thereby
pre-stressing the base material in a longitudinal direction.
In accordance with yet another embodiment, a method is provided for
making an access device that includes forming a layer of flexible
base material defining first and second outer surfaces and a
thickness therebetween; forming one or more elongate support
strands biased to a curvilinear shape; threading the one or more
elongate support strands through the base material, alternately,
between the first and second surfaces and along a length of the
base material.
In accordance with yet another embodiment, a method is provided for
making an access device that includes creating a plurality of
zigzag bands; creating a first layer of flexible base material
including a first surface comprising a plurality of features
corresponding to the shape of the zigzag bands; placing the zigzag
bands against the first surface such that the zigzag bands are
engaged with the features; and applying a second layer of flexible
base material over the zigzag bands and the first layer.
In accordance with another embodiment, an access device is provided
that includes a layer of flexible base material; a plurality of
zigzag bands disposed adjacent one another, one or more flexible
connectors extending between adjacent zigzag bands, the flexible
connectors biased to an original curved shape and embedded within
the base material after elastically lengthening and at least
partially straightening the flexible connectors to a stressed
state, the flexible connectors biased to return towards original
the curved shape, thereby pre-stressing the base material in a
longitudinal direction.
In accordance with still another embodiment, an access device is
provided that includes a layer of flexible base material defining
first and second outer surfaces and a thickness therebetween; and a
plurality of elongate support strands biased to a curvilinear
shape, the support strands threaded through the base material,
alternately, between the first and second surfaces and along a
length of the base material.
Other aspects and features of the present invention will become
apparent from consideration of the following description taken in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate exemplary embodiments, in which:
FIG. 1A is a side view of a silicone sleeve including a plurality
of rings including separable struts embedded therein.
FIG. 1B is a side view of the silicone sleeve of FIG. 1A split
along a length of the sleeve.
FIGS. 2A-2C are top, bottom, and end views, respectively, of the
sleeve of FIG. 1B covered with fabric to provide a cuff defining an
integral penetrable, self-sealing access device.
FIG. 3 is a top view of an exemplary embodiment of a reinforced
patch including elastic support elements embedded in a base
material and surrounded by a sewing ring.
FIGS. 4A-4C are top views of a wall of a vessel, showing a method
for repairing the wall using the patch of FIG. 3.
FIGS. 5A-5C are perspective, side, and end views, respectively, of
an apparatus for delivering an access device, such as the cuff of
FIGS. 2A-2C or the patch of FIG. 3.
FIGS. 6A-6C are perspective views of alternative embodiments of a
blunt dissector that may be included in the apparatus of FIGS.
5A-5C.
FIG. 7A is a side view of an exemplary apparatus for making a
plurality of rings that may be embedded within base material to
provide an access device, such as that shown in FIGS. 2A-2C.
FIGS. 7B and 7C are perspective and side views, respectively, of an
exemplary ring that may be formed using the apparatus of FIG.
7A.
FIG. 8 is a detail of an exemplary embodiment of a mesh pattern for
a set of elastic elements including a connector connecting adjacent
bands that may be incorporated into an access device.
FIGS. 9A and 9B are details of another exemplary embodiment of a
mesh pattern for a set of elastic elements including a connector
connecting adjacent bands that may be longitudinally lengthened and
shortened.
FIGS. 10A and 10B are top and cross-sectional views, respectively,
of a flat mold including a cavity within which a set of elastic
elements have been mounted for making a substantially flat access
device.
FIGS. 11A and 1 lB are end and cross-sectional views, respectively,
of a cylindrical mold including a cavity within which a set of
elastic elements have been mounted for making a generally
cylindrical access device.
FIGS. 12A-12D show exemplary methods for making a substantially
planar access device including a plurality of elastic elements
embedded in base material.
FIGS. 13A-13C are cross-sectional views of a mold showing another
exemplary method for making an access device.
FIGS. 14A-14C show another exemplary method for making an access
device including a plurality of layers of base material thermally
welded around a set of elastic elements.
FIGS. 15A-15D are perspective views of a mold showing an exemplary
method for making a generally cylindrical access device around the
mold.
FIG. 16 is a cross-sectional view of a mold showing another
exemplary method for making a generally cylindrical access device
around the mold.
FIGS. 17A-17C show another exemplary method for making an access
device including a set of elastic elements embedded in base
material.
FIG. 18 is a side view of an exemplary embodiment of a generally
cylindrical access device including a plurality of fingers on ends
of the access device.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
Turning to the drawings, FIGS. 1A-2B show an exemplary embodiment
of a self-sealing access device 330 in the form of a cuff including
a generally annular port body 332 of flexible base material
defining a central longitudinal axis 334, a plurality of bands 350
surrounding or embedded within the port body 332 (FIGS. 1A-1B), and
fabric 360 covering exposed surfaces of the post body 332 (FIGS.
2A-2B). The port body 332 has a generally "C" shaped cross-section
including longitudinal edges 336 extending between first and second
ends 332a, 332b. Alternatively, the port body 332 may be provided
as a patch or other body, e.g., including a substantially planar or
curved surface that may be attached to a tissue structure or other
body structure, as described elsewhere herein and in the
applications incorporated by reference herein.
Optionally, the access device may include one or more additional
features, e.g., to provide a transition between the access device
and an underlying tubular structure to which the access device is
secured. For example, FIG. 18 shows an exemplary embodiment of an
access device 430, e.g., a cuff or sleeve including elastic
elements (not shown) embedded therein, similar to any of the
embodiments described elsewhere herein. The access device 430
includes fingers 432 extending from opposite ends of the
elastomeric material, e.g., to provide greater flexibility, higher
compliances, and/or prevent kinking of the ends when the access
device is implanted on a body structure (not shown).
The port body 332 may be formed from one or more layers of flexible
base material, e.g., silicone, polyurethane, or other elastomeric
or nonporous and/or flexible material. In addition or
alternatively, the port body 332 may be formed from bioabsorbable
material, e.g., polyethylene glycol, PLA, PGA, small intestinal
submucosa (SIS), and the like, as described further in the
applications incorporated by reference herein.
The bands 350 may be formed from continuous rings or "C" shaped
collars of Nitinol or other elastic, superelastic, or shape memory
material formed, e.g., laser cut, mechanically cut, stamped,
machined, and the like, from a tube, wire, or sheet, e.g., similar
to embodiments described in the applications incorporated by
reference herein. Each band 350 may extend at least partially
around the periphery of the port body 332 transverse to the
longitudinal axis 334. For example, each band 350 may include a
plurality of longitudinal struts 352 extending including opposing
ends that are alternately connected to adjacent struts 352 by
curved circumferential connectors, struts, or elements 354, e.g.,
to define a zigzag or other serpentine pattern. The longitudinal
struts 352 may extend substantially parallel to the longitudinal
axis 334 or, alternatively, may extend diagonally or helically
relative to the longitudinal axis 334 (not shown).
Alternatively, the access device 330 may include a contiguous mesh
or other enclosed or open pattern including struts at least
partially surrounding openings (not shown) through which one or
more instruments may be inserted, as described further elsewhere
herein. For example, individual bands or a substantially continuous
mesh sheet may be provided that include interconnected struts
defining generally diamond-shaped or other enclosed openings
therebetween (not shown), with the struts being separable to
increase the size of the openings, e.g., to accommodate receiving
one or more instruments therethrough, as described elsewhere
herein. Exemplary mesh patterns that may be used are shown in U.S.
Pat. Nos. 4,733,665, 5,344,426, and 5,591,197 the entire
disclosures of which are expressly incorporated by reference
herein. In further alternatives, the access device 330 may include
one or more wires or other elongate filaments wound helically or
otherwise around the port body 332 and/or along a desired length of
the port body 332, e.g., a single helical element, multiple helical
filaments braided or otherwise wound together into a mesh, and the
like.
In a further alternative, struts or bands may extend axially along
a length of the access device 330 (not shown). For example, a
plurality of substantially straight wires or other filaments may be
embedded within or otherwise fixed to the base material. The
filaments may be spaced apart sufficiently to accommodate inserting
one or more instruments (not shown) through the access device 330,
with the filaments moving laterally to accommodate the
instrument(s) passing therethrough and resiliently returning to
their original configuration to substantially seal the access
device 330, similar to other embodiments herein. Alternatively, the
filaments may include a zigzag or other pattern that extends
transversely while the filaments extend generally axially between
the ends of the access device 330, e.g., similar to the embodiment
shown in FIG. 17C and described further elsewhere herein. Further,
the filaments or struts may impose a substantially continuous
compressive force on the adjacent base material, which may enhance
sealing any passages created through the base material, also
similar to other embodiments herein and in the applications
incorporated by reference herein.
The struts, filaments, or features of the bands or mesh, e.g., the
struts 352 and curved connectors 354 shown in FIGS. 1A and 1B, may
have any desired cross-section. For example, the features may have
generally round, elliptical, rectangular, or square cross-sections,
optionally, having tapered or rounded surfaces to facilitate
passing an instrument between the features. For example, the
features may be formed with a rectangular cross-section that may
have rounded or tapered edges, e.g., by one or more of
electro-polishing, machining, laser cutting, and the like.
Optionally, the features may have a thickness (extending radially
relative to the central longitudinal axis 334) that is greater than
their width (extending axially and/or circumferentially), which may
provide increased radial support yet accommodate separation of the
features "laterally," as described further elsewhere herein.
In the embodiment shown in FIGS. 1A and 1B, each band 350 has a
generally cylindrical shape, e.g., including first and second
longitudinal ends that are spaced apart axially from one another
and aligned around the periphery of the port body 332, e.g.,
substantially perpendicular to the longitudinal axis 334.
Alternatively, the bands 350 may extend helically around the
periphery of the port body 332 (not shown) and/or may have other
shapes or configurations including an axial length dimension along
a length of the port body 332 and a peripheral dimension extending
at least partially around the periphery of the port body 332.
The bands 350 may be disposed immediately adjacent one another,
e.g., with adjacent bands 350 in phase with one another. For
example, as shown in FIGS. 1A and 1B, the curved connectors 354 on
the first end of a first band 350 may be disposed between the
curved connectors 354 on the second end of an adjacent band 350,
e.g., to partially nest adjacent bands 350. Alternatively, adjacent
bands 350 may be spaced axially apart from one another (not shown),
thereby providing an unreinforced annulus of the port body 332
between adjacent bands 350, which may accommodate introducing
relatively large instruments between the struts 352 and/or bands
350, as described further below. In another alternative, portions
of adjacent bands may overlap one another (not shown) or a braided
or other multiple layer mesh may be provided (also not shown), as
long as struts or other elements of the mesh are free to move
laterally and/or resiliently to accommodate one or more instruments
through openings between the elements. Optionally, in these
embodiments, adjacent bands 350 may be connected to one another by
one or more links or connectors, e.g., similar to those shown in
FIGS. 8-9B and described elsewhere herein.
In a further alternative, adjacent bands 350 may be out of phase
with one another, e.g., such that the curved connectors 354 of
adjacent bands 350 are disposed adjacent one another, e.g., aligned
axially or diagonally relative to one another (not shown). In this
alternative, adjacent bands may define openings surrounded by pairs
of struts from each adjacent band, which may accommodate receiving
relatively large instruments through the openings yet substantially
closing the openings once the instrument(s) are removed.
Optionally, in this alternative, one or more of the curved
connectors 354 on a band 350 may be coupled to one or more curved
connectors 354 of an adjacent band 350. For example, adjacent
curved connectors 354 may be coupled directly together, or may be
coupled by a flexible link or connector (not shown), e.g., to limit
movement of adjacent bands 350 relative to one another.
Alternatively, composite and/or variable materials may be used for
the base material and/or elastic elements to provide varying
compliance at desired locations of the port body 332. For example,
the base material and/or elastic elements may be configured such
that ends or peripheral edges of the resulting access device are
more compliant and/or the compliance varies along the length of the
device. For example, the struts of the elastic elements may be
thinner and/or the base material may have a narrower thickness at
the ends. Such varying compliance may improve the ability of the
resulting access device to accommodate nonlinear and/or tortuous
anatomy.
Turning to FIG. 1A, the access device 330 may be formed by
initially creating a tubular body or sheet of silicone, PET, or
other flexible, nonporous, and/or bioabsorbable base material
having a desired length and/or diameter for the port body 352,
e.g., by one or more of molding, casting, machining, spraying,
spinning, deposition, and the like, as described elsewhere herein.
For example, the tubular body may have a length between about one
and ten centimeters (1-10 cm), a diameter between about one and
forty millimeters (1-40 mm), and a wall thickness between about 0.5
and five millimeters (0.5-5.0 mm).
The set of bands 350 may be formed individually or simultaneously,
e.g., by laser cutting from a tube, winding one or more strands in
a zigzag or other circuitous pattern around a mandrel, and the
like, e.g., as described elsewhere herein. For example, a length of
Nitinol wire or other material 120 may be wound around a
cylindrical mandrel 100 between pins 110 to define a zigzag or
other circuitous pattern to define an enclosed band (or entire set
of bands 122), e.g., as shown in FIGS. 7A-7C and described
elsewhere herein, or may be wound helically along a mandrel to
define a substantially continuous helical band (not shown).
Alternatively, a single tube may be cut to create the set of bands
350 or a substantially continuous mesh of struts (not shown), as
desired. The individual or set of bands 350 may have lengths
between about three and one hundred twenty five millimeters
(3.0-125 mm), e.g., coextensive with or less than the length of the
port body 352.
Alternatively, the bands 350 may be formed from a flat sheet, e.g.,
by one or more of laser cutting, mechanically cutting, etching,
stamping, and the like, to provide one or more sets of struts and
connectors from the sheet, and then rolling the sheet. The
longitudinal edges of the rolled sheet may remain separate, e.g.,
to provide "C" shaped bands, or alternatively the longitudinal
edges may be attached together, e.g., by one or more of welding,
soldering, fusing, bonding with adhesive, using connectors (not
shown), and the like, to provide an enclosed band. In a further
alternative, a set of bands 350, e.g., providing an entire set for
the access device 330, may be formed simultaneously from a tube or
sheet, particularly if the bands 350 are connected together, e.g.,
by links or directly by adjacent connectors 354.
The bands 350 may be heat treated and/or otherwise processed to
provide a desired finish and/or mechanical properties to the bands
350. For example, the bands 350 may be heat treated such that the
bands 350 are biased to a desired relaxed diameter, e.g.,
substantially the same as or smaller than the tubular body for the
port body 332, yet may be resiliently expanded and/or have one or
more struts 352 and/or curved connectors 354 resiliently deformed
to accommodate receiving a needle or other instrument (not shown)
between adjacent struts 352, connectors 354, and/or bands 350, as
described further below. Alternatively, if the bands 350 are formed
from a sheet of material, the sheet may be heat treated and/or
otherwise processed to provide the desired shape and/or properties
for the bands 350 formed from the sheet.
In an exemplary embodiment, for Nitinol material, the bands 350 may
be heat treated such that the A.sub.f temperature for the material
is less than body temperature (about 37.degree. C.), e.g., between
about ten and thirty degrees Celsius (10-30.degree. C.). For
example, the Nitinol material may remain substantially in an
Austenitic state when the access device 330 is implanted within a
patient's body, yet may operate within a superelastic range, e.g.,
transforming to a stress-induced martensitic state when an
instrument is inserted through the openings in the access device
330, as described elsewhere herein. Alternatively, the Nitinol
material may be heat treated to take advantage of the
temperature-activated or other shape memory properties of the
material. For example, the material may be heat treated such that
the bands 350 are substantially martensitic at or below ambient
temperature, e.g., below twenty degrees Celsius (20.degree. C.),
such that the bands 350 may be relatively soft and/or plastically
deformable, which may facilitate manipulation, introduction, or
implantation of the access device 330. At around body temperature,
e.g., at thirty seven degrees Celsius (37.degree. C.) or higher,
the bands 350 may be substantially austenitic, e.g., to recover any
desired shape programmed into the material and to provide elastic
or superelastic properties to the bands 350 once the access device
330 is implanted within a patient's body.
With continued reference to FIG. 1A, to form the access device 330,
a set of bands 350 may be fixed to, e.g., placed on, bonded to, or
embedded in, the tubular body or other base material of the port
body 332, e.g., as described elsewhere herein. For example, in
their relaxed state, the bands 350 may have a diameter smaller than
the base material of the port body 332, and the bands 350 may be
expanded radially outwardly, positioned around the tubular body,
and released such that the bands 350 apply a radially inward
compressive force against the tubular body. Such compression may be
sufficient to bias the port body 332 to a desired diameter, e.g.,
smaller than a tubular body to which the access device 330 may be
secured, for example, to reduce migration and/or otherwise secure
the access device 330. In addition, such compression may impose a
substantially continuous compressive force on the port body 332,
which may enhance the self-sealing function of the access device
330. Alternatively, the bands 350 may be biased to a diameter
similar to the outer surface of the tubular body such that the
bands 350 surround the tubular body without substantial radially
inward compression. In this alternative, the bands 350 may remain
in a substantially relaxed state and/or may not apply a radially
inward compressive force against the base material of the port body
332
Optionally, the bands 350 may be expanded "laterally" in addition
to or instead of being radially expanded. For example, the bands
350 may be expanded radially from a relaxed state to increase the
spacing of the struts or filaments, i.e., increase the size of the
openings defined by the bands 350, and then placed on, embedded in,
and/or otherwise attached to the base material of the port body
332. In this embodiment, once the bands 350 are fixed to the port
body 332, the bands 350 may be released such that the bands 350 are
biased to return laterally inwardly towards the relaxed state,
thereby biasing the struts and openings to a smaller size, yet
accommodating the struts moving laterally to accommodate an
instrument being inserted through the openings, as described
elsewhere herein.
As described above, once fixed to the port body 332, the bands 350
may be spaced apart from, may contact, may overlap, or may be
nested between adjacent bands 350, e.g., in phase or out of phase
with one another, as desired. Alternatively, if the bands 350 are
connected to one another, the entire set of bands 350 may be
positioned around the tubular body with or without expanding and
releasing the bands.
Optionally, with the bands 350 surrounding, placed against, and/or
fixed relative to the base material of the port body 332, another
layer of silicone, PET, or other flexible base material may be
applied around the bands 350 to further form the port body 332,
thereby embedding the bands 350 within the base material. For
example, an outer layer of silicone may be applied around the bands
350 and the assembly may be heated, cured, or otherwise processed
to fuse, melt, or otherwise bond the material of the outer layer to
the bands 350 and/or the material of the tubular body, e.g., as
shown in FIGS. 14A-14C and described elsewhere herein.
Alternatively, the tubular body may be softened or otherwise
treated to allow the bands 350 to become embedded therein, or the
tubular body may be formed around the bands 350, if desired. In a
further alternative, the bands 350 may be secured around the
tubular body, e.g., by one or more of bonding with adhesive, sonic
welding, fusing, and the like.
As shown in FIGS. 1A and 1B, a plurality of bands 350 are embedded
in or secured around the port body 332, e.g., two, three, four,
five (as shown), or more bands 350, as desired. For example, as
shown, the bands 350 may be provided along substantially the entire
length of the port body 332. Alternatively, the bands 350 may be
provided only in a central region of the port body 332, e.g., with
regions adjacent the first and second ends 332a, 332b including
unsupported silicone or other base material (not shown) and/or
fingers or other transition features, such as the fingers 432 shown
in FIG. 18.
Returning to FIGS. 1A and 1B, once the bands 350 are embedded
within or otherwise secured to the port body 332, the port body 332
may be split or otherwise separated, e.g., by one or more of laser
cutting, mechanical cutting, and the like, through the silicone
material and the bands 350, to provide the side edges 336, as shown
in FIG. 1B. Alternatively, the bands 350 may be formed as
discontinuous "C" shaped collars that may be attached around or
embedded within the port body 332 before or after splitting the
port body 332 to create the longitudinal edges 336. In a further
alternative, a length of base material with embedded bands
corresponding to multiple individual access devices may be formed
using the methods described above, and the resulting assembly may
be cut or otherwise separated into individual port bodies 332, if
desired. In yet a further alternative, the bands and port bodies
may not be cut longitudinally, if a tubular access device is
desired, similar to other embodiments herein.
Turning to FIGS. 2A-2C, fabric 360 may be applied over any exposed
surfaces, e.g., over the outer, inner, and end surfaces of the port
body 332 to provide the completed access device 330. For example,
one or more pieces of fabric 160 may be wrapped around the port
body 332 and stitched together and/or to the port body 332, e.g.,
similar to embodiments in the applications incorporated by
reference herein. Optionally, the access device 330 may include one
or more tactile elements, ferromagnetic elements, echogenic
elements, and the like (not shown), e.g., to facilitate locating
the access device 330 and/or bands 350 when the access device 330
is implanted subcutaneously or otherwise within a patient's body,
such as those disclosed in the applications incorporated by
reference herein.
During use, the access device 330 may be positioned around a
tubular structure, e.g., a graft before or after implantation, a
blood vessel, fistula, or other tubular structure (not shown)
exposed or otherwise accessed within a patient's body. For example,
the side edges 336 may be separated, and the port body 332
positioned around or otherwise adjacent a tubular structure. The
side edges 336 may be released to allow the port body 332 to
resiliently wrap at least partially around the tubular structure
and/or the port body 332 may be attached to the tubular structure,
e.g., by one or more of bonding with adhesive, suturing, fusing,
and the like. Alternatively, if the access device includes an
enclosed tubular port body (not shown), the access device may be
directed over a tubular structure from one end thereof (which may
be preexisting or may be created by cutting the tubular
structure).
In an alternative embodiment, an access device similar to access
device 330 may be attached to a tubular graft or other structure
before introduction and/or implantation within a patient's body. In
another alternative, the access device 330 may be integrally formed
into the wall of a graft, e.g., during manufacturing of the graft,
if desired. For example, rather than providing a separate port body
332, the bands 350 or other support elements may be integrally
molded or otherwise embedded within a wall of a tubular graft or
other implant. Thus, the implant may include an integral access
device that operates similar to the other embodiments herein.
Returning to FIGS. 2A-2C and with reference to the access device
330, if it is desired to access a lumen of the tubular structure, a
needle (not shown) may be introduced through the patient's skin
over the access device 330, and directed through the port body 332
into the lumen. The thickness of the access device 330 may
facilitate identifying the ends of the access device 330, e.g., by
palpation, since the ends may be identified tactilely relative to
the adjacent regions of the tubular structure. Thus, the access
device 330 may reduce the risk of accidental sticks in regions of
the tubular structure not covered by the access device 330.
As the needle is inserted, if the needle encounters any of the
struts 352, connectors 354, or other features of the bands 350, the
encountered features may resiliently move away from the needle to
create a passage through the access device 330 into the lumen. If
one or more larger instruments are subsequently introduced through
the access device 330, e.g., over a guidewire advanced through the
needle or over the needle itself, the struts 352, connectors 354,
and/or other features of the bands 350 may resiliently separate to
create a sufficiently large passage through the port body 332 to
accommodate the instrument(s). Generally, the struts 352,
connectors 354, and/or other features of the bands 350 separate
"laterally," i.e., circumferentially and/or axially within the
cylindrical surface defined by the port body 332, to provide a
passage through the port body 332. As used herein, "laterally"
refers to movement of the features of the bands 350 or other mesh
substantially in a direction around the circumference and/or along
the length of the port body 332 within the base material and
generally not out towards the inner or outer surfaces of the port
body 332 (i.e., "within the plane" of the port body 332). For
example, if the port body 332 were substantially flat within a
plane, laterally would refer to movement of the features of the
bands substantially within the plane and generally not out of the
plane towards the inner or outer surfaces.
After a procedure is completed via the access device 330 and the
lumen of the tubular structure, any instruments may be removed,
whereupon the bands 350 may resiliently return towards their
original shape, e.g., laterally inwardly towards their original
configuration, thereby compressing the base material of the port
body 332 to close any passage created therethrough. Thus, the bands
350 may provide a self-sealing or self-closing feature that
automatically substantially seals any passages created through the
port body 332 by a needle or other instruments.
For example, if the spacing of the struts or other features of the
bands 350 is smaller than the cross-section of the instrument(s)
inserted through the access device 330, the features may separate
to create a passage through the access device 330 that is larger
than the spacing of the features in their relaxed state. However,
even if the spacing of the features is larger than the
cross-section of the instrument(s) inserted through the access
device 330, the bands 350 may provide sufficient bias within the
plane of the port body 332 to bias the port body material to
resiliently close laterally inwardly around any passage created
therethrough to automatically close the passage. Thus, the
elasticity/bias of the bands 350 may reinforce and/or bias the
material of the port body 332 to allow repeated access through the
access device 330, while automatically closing any passages to
self-seal the access device 330. The bias or support of the port
body material between the struts of the bands 350 may also reduce
the risk of the material breaking down over time due to multiple
penetrations.
One of the advantages of the access device 330 is that a needle or
other instrument may be introduced at multiple locations through
the port body 332. As long as the needle is inserted through a
region of the access device 330 including and/or supported by one
or more bands 350, the features of the bands 350 may separate or
otherwise open to accommodate the needle and resiliently return
towards their substantially stress free or preloaded original
configurations when all instruments are removed.
In addition, such bands 350 may protect the accessed tubular
structure from over-penetration of needles or other instruments.
For example, if the access device 330 substantially surrounds the
tubular structure, a needle or other instrument that is
inadvertently inserted into one side of the access device 330
through the entire tubular structure and out the opposite side of
the access device 330 may be removed without substantial risk of
bleeding or other leakage from the posterior location as well as
the anterior location since the access device 330 may self-seal
both openings.
Optionally, if the port body 332 has a periphery defining less than
one hundred eighty degrees (180.degree.) or is substantially flat,
the access device 330 may be applied as a patch to the surface of
any body structure, e.g., a tubular structure, such as a graft,
fistula, blood vessel, and the like, or to an organ, abdominal
wall, or other tissue structure. The "patch" may have a variety of
shapes and/or sizes depending upon the application and/or may have
sufficient flexibility to conform to the shape of anatomy to which
the patch is applied. For example, the port body 332 may have a
two-dimensional shape, e.g., a rectangular, square, oval, or
circular shape, with bands 350 provided along the entire surface
area of the port body 332 or spaced apart inwardly from an outer
perimeter of the "patch." Such patches may be created by cutting or
otherwise separating a desired shape from the tubular body
described above after embedding or securing bands thereto.
Alternatively, individual patches may be created by embedding or
securing flat bands to patches of silicone or other base material
formed into the desired shape.
In a further alternative, the patch may be created by laminating
multiple layers of material to create a self-sealing structure that
may be attached to a tissue structure. For example, each layer may
include elastic support elements, e.g., a mesh, struts, and the
like, that support one or more layers of base material within a
plane of the base material(s). Alternatively, one or more layers of
base material may be provided that has sufficient flexibility and
bias such that the support elements may be omitted.
The resulting patch may accommodate creating an opening through the
base material(s) of the layers when one or more instruments are
inserted through the patch, i.e., with the support elements moving
laterally within the plane of the base material(s). After removing
the instrument(s), the support elements may bias the base
material(s) of the respective layers laterally towards their
original configuration, thereby automatically closing the
opening.
Alternatively, the access device 330 may be provided in a
three-dimension configuration, e.g., a conical, parabolic, or other
shape (not shown). In addition or alternatively, the access device
330 may be provided in a curved cylindrical (e.g., substantially
uniform or tapered) or other shape having a desired arc length,
e.g., up to sixty degrees (60.degree.), one hundred twenty degrees
(120.degree.), between five and three hundred sixty degrees
(5-360.degree.), between one hundred eighty and three hundred sixty
degrees (180-360.degree.), and the like. The port body 332 may be
biased to a predetermined three-dimensional shape yet sufficiently
flexible to accommodate the actual anatomy encountered, e.g.,
having one or more bands or other structures including elastic
struts embedded within or otherwise secured to a flexible base
material, such as silicone, polyurethane, or other elastomer,
similar to other embodiments herein.
Optionally, the access device 330 may be used as a patch or
surgical mesh, e.g., which may be attached or otherwise secured to
weakened areas of tissue or organs to provide reinforcement in
addition to allowing subsequent access, if desired. For example,
the access device 330 may be applied as a patch for vascular
repair, e.g., over a pseudo-aneurysm, or after excising a
pseudo-aneurysm to reinforce the region and/or allow subsequent
access.
Turning to FIG. 3, an exemplary embodiment of a surgical patch 530
is shown that includes one or more layers of base material 532,
e.g., defining a substantially flat or curved "plane," and a
plurality of support elements or bands 550 embedded or otherwise
attached to the base material 530. For example, the base material
532 may include one or more layers of silicone or other elastomeric
material that may be biased to a flat or curved planar shape or may
be "floppy," i.e., may have no particular shape and may conform
substantially to any desired shape. As shown, the support elements
include a plurality of bands 550 including features, e.g., struts
552 alternately connected by curved connectors 554, similar to
other embodiments herein. The bands 550 may extend along a
substantially linear axis across the base material 532, e.g.,
defining a sinusoidal or other alternating pattern, adjacent to and
substantially parallel to one another. Thus, the features, e.g.,
struts 552 and connectors 554, may support the base material 532,
such that the support elements 550 may be separable laterally to
accommodate receiving one or more instruments (not shown) through
the base material 532, yet resiliently biased to close any openings
through the base material 532 created by the instrument(s), similar
to other embodiments herein.
Alternatively, the patch 530 may include one or more layers of base
material 532 without the support elements 550 covered with fabric
or other material (not shown). The base material 532 may be
constructed to be self-supporting and resiliently biased to allow
the creation of passages therethrough by a needle or other
instrument (not shown), yet self-close the passage(s) upon removal
of the instrument(s) to prevent substantial leakage through the
patch 530. For example, each layer of base material may provide
axial strength in a desired axial direction, and multiple layers
may be attached together with the axial directions orthogonal or
otherwise intersecting one another. The direction of axial strength
may be achieved by selection of the polymer or other material for
the base material or by embedding strands, wires, or other axial
elements within the base material (not shown). Similar to other
embodiments herein the patch 530 may be biased to a substantially
flat configuration, a curved configuration, or may be "floppy," as
described elsewhere herein.
In addition, as shown in FIG. 3, the surgical patch 530 may include
a sewing ring or cuff 560 extending around a periphery of the base
material 532, e.g., to facilitate securing the patch 530 to tissue,
as described further below. For example, the sewing ring 560 may
include one or more layers of fabric or other material, e.g.,
optionally filled with foam, fabric, or other resilient, flexible,
and/or penetrable material, attached to the periphery of the base
material 532, e.g., by stitching with sutures, bonding with
adhesive, and the like. The base material 532 may also be covered
with fabric or other material, e.g. the same or different material
than the sewing ring 560, to enhance tissue ingrowth and/or
integrate the components of the patch 530.
The patch 530 may have a generally round shape, e.g., an
elliptical, oval, or substantially circular shape. Alternatively,
the patch 530 may have a square or other rectangular shape, or
other geometric shape, as desired.
In an alternative embodiment, the patch 530 may be provided in a
"cut-to-length" configuration, e.g., an elongate sheet or roll (not
shown) of base material 532, having a predetermined width and a
length sufficient to provide multiple individual patches. In this
alternative, the sewing ring 560 may be omitted or may be provided
along the longitudinal edges of the sheet or roll. Optionally, the
sheet or roll may include weakened regions to facilitate separating
individual patches or may include unsupported regions without
support elements 550 between regions with support elements 550,
e.g., that may be easily cut otherwise separated to allow
individual patches to be separated from the sheet or roll.
Turning to FIGS. 4A-4C, an exemplary method is shown for vascular
repair using the patch 530 of FIG. 3. As shown in FIG. 4A, a blood
vessel 90 may include a weakened region 92 in need of repair.
Turning to FIG. 4B, the weakened region 92 and adjacent tissue may
be resected to create an opening 94, e.g., corresponding to the
size and shape of the patch 530. The patch 530 may then be attached
within or over the opening 94, e.g., by suturing the sewing ring
560 to the vessel wall surrounding the opening 94. Alternatively,
the patch 530 may be attached to the wall of the vessel 90 without
removing the weakened region 92, e.g., by attaching the patch 530
to the vessel 90 over the weakened region 92 or within the lumen
underlying the weakened region 92, thereby supporting the weakened
region 92. In another alternative, the patch 530 may be attached to
a vessel wall that does not include a weakened region, e.g., as a
prophylactic measure to prevent a weakened region from developing
at the site of implantation. The patch 530 may thereafter provide a
structure for supporting the vessel wall and/or provide a
self-closing structure allowing multiple access to the vessel 90,
similar to other embodiments herein.
In another embodiment, an access port patch may be attached to the
apex of the left ventricle of a heart to facilitate trans-apical
procedures, e.g., aortic valve replacement, and the like. Such a
patch may allow one-time or repeated access through the LV apex
into the left ventricle. Once the procedure is completed, any
instruments introduced through the patch may be removed, and the
patch may provide substantially instantaneous sealing of the LV
apex.
In another option, the access device 330 may be provided in a
tubular or "C" shaped configuration, and may be introduced into a
blood vessel or other body lumen. For example, the access device
330 may be rolled or otherwise compressed, and loaded into a
catheter, delivery sheath, and the like (not shown). Alternatively,
the access device 330 may be advanced over a needle, e.g., a
dialysis needle, into the interior of a graft, fistula, or other
tubular structure after dialysis. Once deployed within a lumen of a
tubular structure or body lumen, the access device 330 may be
attached to the wall of the body lumen, e.g., by one or more of
stitching with sutures, bonding with adhesive, interference fit due
to the radial bias of the access device 330, and the like. Thus,
the access device 330 may provide an immediate barrier to leakage
through a wall of the body lumen, e.g., to substantially seal a
puncture site from the interior of the body lumen. In addition, the
access device 330 may allow the lumen to be subsequently accessed
again, as desired, with the access device 330 providing a
self-sealing access region, similar to other embodiments
herein.
Turning to FIGS. 5A-5C, an exemplary embodiment of an apparatus 10
is shown for implanting an access device 330, e.g., a cuff or
patch, such as those described elsewhere herein and in the
references incorporated by reference herein. Generally, the
apparatus 10 includes a dissector 20 carrying the access device 330
and a constraint 30 for releasably securing the access device 330
to the dissector 20.
The dissector 20 generally includes a proximal end, e.g., including
a handle (not shown), and a distal end or portion 24 having a "C"
shaped cross-section and including longitudinal edges 27 defining a
slot, thereby defining a lumen or passage 28 therein for receiving
a body structure, e.g., a blood vessel, fistula, tubular graft, and
the like (not shown). In an exemplary embodiment, the distal end
portion 24 of the dissector 20 terminates in a substantially
atraumatic and/or blunt distal tip 26, e.g., to provide a blunt
dissection edge, which may facilitate placement of the access
device 330 on or around a body structure. For example, the blunt
distal tip 26 may allow tissue or other material attached to or
disposed adjacent the outer surface of the body structure to be
removed, dissected, and/or otherwise directed away from the body
structure, e.g., to provide a target implantation site for the
access device 330. Alternatively, the distal tip 26 may include a
sharpened or other edge to enhance dissection or cutting tissue, if
desired.
The "C" shaped distal end portion 24 of the dissector 20 may have a
length longer than the access device 330, e.g., such that the
entire access device 330 may be supported and/or otherwise carried
on the outer surface of the distal end 24. Proximally, the
dissector 20 may transition to a shaft or other structure coupled
to the handle and/or proximal end, e.g., to facilitate manipulation
of the apparatus 10. Optionally, the handle or proximal end may
include one or more markers (not shown) to identify the orientation
of the distal end portion 24, e.g., to facilitate a user
identifying the orientation of the longitudinal edges 27 and/or the
location of the slot when the distal end portion 24 is introduced
into a patient's body.
The distal end portion 24 may have sufficient column strength to be
advanced or otherwise manipulated from the proximal end, yet may
have sufficient flexibility to be introduced and/or positioned as
desired, e.g., around a body structure within a patient's body. For
example, the distal end portion 24 may be sufficiently flexible
such that the longitudinal edges 27 may be separated to accommodate
a body structure being received through the slot into the interior
28 of the dissector 20. In an exemplary embodiment, the distal end
24 portion may have a cross-section defining a portion of a circle
or other arcuate shape, e.g., extending up to or greater than
180.degree. around the periphery of the target body structure,
having a diameter corresponding to the body structure such that the
longitudinal edges 27 may resiliently separate and then wrap around
and/or engage the body structure to dissect surrounding tissue.
FIGS. 6A-6C show exemplary embodiments that may be provided for the
distal end portion 24 of the dissector 20. For example, FIG. 6A
shows a "C" shaped tube 20, e.g., a tubular structure that may have
the slot formed therein, e.g., by cutting, molding, and the like,
terminating in a substantially blunt distal tip 26. FIG. 6B shows a
"C" collar defining the distal tip 26' and a plurality of spring
elements extending proximally from the distal tip 26,' e.g., to
carry the access device 330 and support the distal tip 26.' FIG. 6C
shows a "C" shaped spring element 20,'' e.g., including a plurality
of "C" shaped wires or other structures connected sequentially to
one another along the distal end and terminating in a blunt distal
tip 26.'' Such spring elements may provide flexibility to
accommodate bending, e.g., during introduction of the dissector
20,' 20'' while providing sufficient column strength or axial
stiffness to allow dissection when advanced.
The constraint 30 may include one or more structures for releasably
securing the access device 330 to the dissector 20. For example, as
shown, the constraint includes a plurality of fingers 31 extending
from an inner collar or sleeve that may engage a proximal end of
the access device 330 and an outer sleeve 34 or other structure
that may press the fingers 31 inwardly to hold the access device
330 relative to the dissector 20, e.g., to prevent the access
device 330 from rotating and/or sliding axially relative to the
distal end 24. In an exemplary embodiment, the outer sleeve 34 may
be advanced to compress the fingers 31 to apply an inward force
between the access device 330 and the outer surface of the distal
end portion 24, e.g., to frictionally secure the access device 330
to the distal end portion 24. The sleeve 34 may be retracted to
remove the force from the fingers 30, thereby removing the friction
or other force between the access device 330 and the dissector 20,
e.g., to allow the dissector 20 to be withdrawn proximally relative
to the access device 330.
Optionally, as shown in FIG. 5B, the constraint 30 may include one
or more stops 32, e.g., on an inner surface of one or more (e.g.,
each) of the fingers 31, to prevent proximal migration when the
distal end portion 24 of the dissector 20 is removed proximally
from within the access device 330. For example, a plurality of tabs
or ridges 32 may be provided on inner surfaces of the fingers 31,
which may abut the proximal end of the access device 330. Thus, if
the dissector 20 is removed, e.g., after positioning the dissector
20 and access device 330 around a body structure, the proximal end
of the access device 330 may contact the tabs or ridges 32, thereby
maintaining the access device 330 substantially in place around the
body structure. The access device 330 may thus slide off the distal
end portion 24 and be received around the body structure.
Alternatively, other constraints may be provided on the dissector
20 to releasably secure and/or prevent proximal migration of the
access device 330. For example, an outer sleeve, e.g., having a "C"
shaped cross-section (not shown) may be provided over the access
device 330, e.g., including a stop to allow withdrawal of the
dissector 20. In another embodiment, one or more filaments (not
shown) may be wrapped around the access device 330 and/or dissector
20 to secure the access device 330. The filament(s) may be cut or
otherwise removed, e.g., to release the access device 330 and/or
allow removal of the dissector 20.
During use, the access device 330 may be loaded or otherwise
provided on the distal end portion 24 of the dissector 20. In one
embodiment, the access device 330 may have an inner diameter and/or
a perimeter smaller than the distal end portion 24, e.g., such that
longitudinal edges 336 of the access device 330 do not extend
entirely around the distal end portion 24, for example, offset from
the longitudinal edges 27 of the dissector 20, as shown in FIG. 5C.
For example, the access device 330 may apply a radially inward
force against the outer surface of the distal end portion 24.
Alternatively, the access device 330 may have an inner diameter
similar to the outer diameter of the distal end portion 24 such
that the access device 330 is in a substantially relaxed condition
around the distal end portion 24.
The distal end portion 24, carrying the access device 330, e.g.,
secured by the constraint 30, may be introduced into a patient's
body to implant the access device 330. For example, the distal end
portion 24 may be introduced directly through a percutaneous
incision or other opening in the patient's skin towards a target
location, e.g., a body structure beneath the skin, such as a blood
vessel, fistula, or tubular graft (not shown). Alternatively, the
distal end portion 24 may be introduced through another device
previously placed between the patient's skin and the target
location, e.g., an endoscope, introducer sheath, and the like (not
shown).
A portion of the body structure may be received through the slot
between the longitudinal edges 27 into an interior 28 of the
dissector 20, e.g., to position the access device 330 around the
body structure. If the slot has a smaller width than the body
structure, the distal end portion 24 may be directed around the
body structure with the longitudinal edges 27 opening to
accommodate receiving the body structure through the slot into the
interior 28. The distal end portion 24 may be sufficiently flexible
to allow the distal tip 26 to contact the body structure at an
angle, thereby opening the slot at the tip 26 and then opening the
slot proximally along the distal end portion 24 as the body
structure passes through the slot.
The distal end portion 24 may be advanced along the body structure,
e.g., to dissect adjacent tissue from an outer surface of the body
structure, e.g., to provide a portion of the body structure free
from tissue adhesions or other undesired materials on its outer
surface. In this manner, the distal end portion 24 may be advanced
and/or otherwise manipulated to position the access device 330 over
or around a desired section of the body structure.
The dissector 20 may then be removed, to release the access device
330 around the body structure. For example, as described above, the
constraint 30 may be removed or otherwise actuated to release the
access device 330 from the distal end portion 24, whereupon the
dissector 20 may be withdrawn proximally along the body structure
while the access device 330 remains substantially in place around
the body structure. Once the dissector 20 is removed from within
the access device 330, the dissector 20, constraint 30, and/or
other components of the apparatus 10 may be removed, leaving the
access device 330 in place. Optionally, the access device 330 may
be further secured to the body structure, e.g., using one or more
of sutures, adhesives, and the like, as described elsewhere herein
and in the applications incorporated by reference herein.
A number of methods can be used to make the access devices
described herein and in the applications incorporated by reference
herein. For example, FIGS. 7A-7C show an exemplary method for
making an elastic element in the form of a ring that may be
included in an access device, such as the cuff of FIGS. 2A-2C. As
shown in FIG. 7A, an elongate cylindrical mandrel 100 may be
provided that includes multiple sets of pins 110 arranged in a
predetermined pattern around the periphery of the mandrel 100,
e.g., including a first annular set, a second annular set offset
axially from the first annular set, a third set, and the like.
A wire or other filament or strand 120 (e.g., formed from Nitinol
or other material, as described elsewhere herein) may be wound
around a first set of pins 110 of the mandrel 100, e.g.,
circumferentially in a zigzag pattern, and then offset to and wound
around a second set of pins, etc., based on the number of sets of
pins 110 provided on the mandrel 100. The winding may be repeated
to provide a tubular structure 122 including a plurality of annular
rings 150 of zigzag elements spaced apart axially from one
another.
Optionally, the tubular structure 122 may be heat treated or
otherwise further processed while remaining on the mandrel 100. In
this option, the mandrel 100 should be formed from materials able
to withstand any processing parameters. Once a desired number of
rings 150 have been formed (corresponding to the number of sets of
pins 110), the tubular structure 122 may be removed from the
mandrel 100. For example, given the elasticity of the strand 120,
the tubular structure 122 may simply be elastically stretched and
pulled off from around the pins 110 and mandrel 100. Alternatively,
the pins 110 may be removable or retractable into the mandrel 100
(not shown) to accommodate removal after forming the tubular
structure 122.
Turning to FIG. 7B, the tubular structure 122 of FIG. 7A may be
separated into a plurality of rings of zigzag elements (one ring
150 shown) including free ends. For example, the wire 120 may be
cut or otherwise severed between each ring 150 and any portions of
the wire 120 defining connectors between each ring 150 and any
excess beyond the last rings may be severed, thereby providing
multiple separate rings 150, each with free ends 152, as shown in
FIG. 7B. As shown in FIG. 7C, the free ends 152 of each ring 150
may be attached together, e.g., by being inserted and crimped in a
hypotube or other sleeve 154, or alternatively by welding, bonding
with adhesive, and the like (not shown). The resulting ring(s) 150
may be heat treated, further processed, and/or incorporated into an
access device (not shown), as described elsewhere herein and in the
applications incorporated by reference herein. Alternatively, the
tubular structure 122 may be incorporated into an access device
without separating the individual rings 150.
For example, the individual ring(s) 150 (or entire tubular
structure 122) may be embedded in or otherwise combined with a base
material to provide a tubular sleeve for an access device, e.g.,
using the methods described elsewhere herein. Optionally, the
resulting tubular sleeve may be cut longitudinally, e.g., to
provide a cuff or may be used to form a tubular access device, as
described elsewhere herein. Alternatively, the ring(s) 150 shown in
FIG. 7B may be used without attaching the free ends 152. For
example, the ring(s) 150 may be shape set in a "C" shape, a curved
shape, or a substantially flat shape with the free ends 152 spaced
apart, e.g., corresponding to a desired diameter or other shape of
an access device (not shown), and may be embedded in or otherwise
combined with base material, e.g., using the methods described
elsewhere herein. Thus, the free ends 152 may be disposed along
longitudinal edges of an access cuff or other access device.
A similar process may be used for forming substantially flat or
arcuate elastic elements. For example, a substantially flat or
curved mandrel may be provided with multiple set of pins (not
shown) arranged in a predetermined pattern across a surface of the
mandrel, e.g., including a first set, a second set offset axially
from the first set, etc. A wire may be wound around the pins to
provide adjacent zigzag elements connected and/or offset from one
another, which may remain together or may be separated into
separate zigzag elements for incorporation into an access device
(not shown).
Turning to FIG. 8, a detail is shown of another exemplary
embodiment of a mesh pattern for an access device (not shown) in
which adjacent sets of elastic elements (e.g., rings) are connected
to one another. As shown, the mesh pattern may include zigzag
elements 250 adjacent one another with each zigzag element defining
an enclosed or open ring or a substantially flat or curved elastic
element with free ends (not shown). Similar to other embodiments,
each zigzag element 250 may include substantially straight or
generally longitudinal struts 252 connected at alternating ends by
curved struts 254, thereby defining a serpentine or other zigzag
pattern.
One or more connector elements 256 may couple adjacent sets of
zigzag elements 250, e.g., extending between longitudinally
adjacent curved struts 254, which may be thinner and/or more
flexible than the struts 252, 254 of the elastic elements 250. In
an exemplary embodiment, a single connector element 256 may connect
adjacent zigzag elements 250. The connector element(s) 256 may be
substantially straight having a length slightly greater than the
distance between the adjacent curved struts 254 that are coupled
together, or may have a curvilinear shape defining an overall
length greater than the distance between the adjacent curved struts
254, e.g., providing additional flexibility and/or adjustability
between the adjacent zigzag elements 250.
The connector element(s) 256 may allow a plurality of zigzag
elements 250 to be fabricated together, e.g., by laser cutting,
chemical etching, EDM, water jet, and the like. For example, a tube
or sheet of material may have unwanted material removed to result
in a desired arrangement of zigzag elements 250 and connector
elements 256 that are integrally formed together. The connector
elements 256 may provide substantially no structure, but may simply
keep the zigzag elements 250 together during subsequent processing
and/or incorporation into an access device (not shown). For
example, during electro-polishing, the connector elements 256 may
provide a conductive path allowing electrical current to pass
between the zigzag elements 250, allowing all of the zigzag
elements 250 to be processed together.
Thus, the zigzag elements 250 may be manually or otherwise
manipulated together during processing, e.g., to set a shape and/or
pre-stress the zigzag elements 250, as described elsewhere herein.
After processing, the zigzag elements 250 may be incorporated into
an access device, e.g., by embedding into base material, with the
connector elements 256 remaining intact (but providing little
limitation on subsequent movement of the zigzag elements 250 during
use of the access device given their flexibility). The connector
elements 256 may facilitate loading and/or positioning the zigzag
elements 250 before or during incorporation into base material
since the zigzag elements 250 remain coupled together yet may be
adjusted relative to one another. The connector elements 256 may
also be sufficiently flexible to accommodate adjusting the distance
between adjacent zigzag elements 250, e.g., allowing the zigzag
elements 250 to be partially nested together, if desired, during
incorporation into the base material. Alternatively, the connector
elements 250 may be severed and/or removed and individual zigzag
elements may be incorporated into an access device, as described
elsewhere herein.
Turning to FIGS. 9A and 9B, details of another exemplary embodiment
of a mesh pattern for an access device is shown in which adjacent
sets of elastic elements (e.g., rings or other zigzag elements
250') are connected together. As shown, the mesh pattern may
include zigzag elements 250' adjacent one another with each zigzag
element defining an enclosed or open ring or a substantially flat
or curved elastic element with free ends (not shown). Similar to
other embodiments, each zigzag element 250' may include
substantially straight or generally longitudinal struts 252'
connected at alternating ends by curved struts 254,' thereby
defining a serpentine or other zigzag pattern.
One or more connector elements 256' may couple adjacent zigzag
elements 250,' e.g., extending between longitudinally adjacent
curved struts 254.' For example, each curved strut 254' may be
connected to the adjacent curved strut 254' by a connector element
256' to provide a closed-cell mesh, or only some (e.g., ever other,
every third, etc.) of the curved struts 254' may be connected by a
connector element 256' to provide an open-cell mesh.
The connector elements 256' may have an initial, relaxed shape,
e.g., a curvilinear shape as shown in FIG. 9A, and may be
resiliently manipulated to a pre-stressed shape, e.g., a
substantially straight shape as shown in FIG. 9B. For example, the
sets of elastic elements 250' may be extended along a longitudinal
axis 234' of the resulting access device to increase the overall
length of the elastic elements 250,' e.g., to provide a
longitudinal pre-stress when the elastic elements 250' are
incorporated into an access device. In addition or alternatively,
the sets of elastic elements 250' may be expanded radially,
circumferentially, or otherwise transverse to the longitudinal axis
234,' similar to other embodiments herein, thereby pre-stressing
the elastic elements 250' laterally, e.g., to bias the elastic
elements 250' towards a smaller diameter or lateral length.
In the pre-stressed condition, e.g., with the connector element(s)
256' at least partially straightened as shown in FIG. 9B, adjacent
elastic elements 250' may remain partially nested with each other,
e.g., such that there is overlap between the nearest curved struts
254 of the adjacent elastic elements 250.' When the connector
element(s) 256' are released, e.g., after being embedded into base
material or otherwise incorporated into an access device, the
connector element(s) 256' may bias the adjacent elastic elements
250' towards the nested position, such as that shown in FIG. 9A.
Optionally, the thickness of the struts 252,' 254,' 256' and/or the
radius of the curved struts 254' may be adjusted, as desired, to
modify the stiffness and/or bias of the resulting access
device.
Any of the elastic elements described herein and in the
applications incorporated by reference herein may be embedded or
otherwise incorporated into base material and covered with fabric
or other covering to provide an access device. In one method, the
elastic elements may be placed within a mold and base material
injected into the mold to encase the elastic elements in the base
material.
For example, turning to FIGS. 10A and 10B, an exemplary embodiment
of a flat mold 600 is shown that includes a pair of mold plates 602
defining a cavity 604 therebetween within which a set of elastic
elements 650 have been mounted, e.g., under tension or other
pre-stressed state, or in a relaxed state. As shown, extended ends
658 of the set of elastic elements 650 may be secured within end
regions 608 of the mold 600 such the elastic elements 650 are
suspended or otherwise arranged within the cavity 604 as
desired.
Elastomer or other base material (not shown) may be injected into
the cavity 604, e.g., via injection ports 606, to encase the
elastic elements 650 and create a panel for an access device (e.g.,
after securing a fabric covering around the panel, not shown),
similar to other embodiments herein and in the applications
incorporated by reference herein. As shown, the mold 600 may
include multiple injection ports 606, e.g., at each end of the
cavity 604 and/or in one or both mold plates 602, which may reduce
time to inject the base material and/or provide substantial
uniformity when filling the cavity 604. The depth of the recesses
defining the cavity 604 in the mold plates 602 may be selected to
provide a desired thickness for the resulting access device, which
may be substantially uniform or may variable, as desired. Once the
base material is injected and cured, as desired, the mold plates
602 may be opened, and the encased elastic elements 650 removed and
processed further to provide the final access device (not shown),
e.g., removing the extended ends 658, adding a fabric covering (not
shown), and the like.
Turning to FIGS. 11A and 11B, an embodiment of a cylindrical mold
700 is shown including a plurality of mold plates 702, 703 defining
an annular cavity 704 within which a set of elastic elements 750
have been mounted, e.g., under tension or otherwise pre-stressed,
similar to other embodiments herein. For example, the set of
elastic elements 750 may include extended ends 758 that may be
secured within end regions 708 of the mold 700, e.g., similar to
the flat mold 600 of FIGS. 10A and 10B.
As best seen in FIG. 11B, the mold 700 may include a hollow mold
core 702 including a passage 702a communicating with injection
ports 706 that, in turn, communicate with the interior of the
cavity 704. The mold 700 also includes one or more outer mold
plates 703, e.g., a pair of plates that may be secured around the
core 702 and the set of elastic elements 750, recesses of the core
702 and plates 703 together defining the cavity 704.
Elastomeric or other base material (not shown) may be injected into
the cavity 704 via the core passage 702a and injection ports 706,
to encase the elastic elements 750 and create a sleeve for an
access device (not shown), similar to other embodiments herein and
in the applications incorporated by reference herein. The elastic
elements 750 may be mounted within the cavity 704 in a
substantially relaxed state or in a pre-stressed state, e.g.,
resiliently radially expanded and/or longitudinally stretched
across the cavity 704 to pre-stress the elastic elements 750 in a
desired manner when encased in the elastomeric material.
Alternatively, a multiple step molding process may be used, e.g.,
to first create a base layer (not shown) either inside or outside
the elastic elements 750, which may support the elastic elements
750, e.g., to maintain a substantially uniform diameter or other
configuration. In a further alternative, the elastic elements 750
may be mounted on an elastomeric base (also not shown), e.g., on an
outer surface of an elastomeric tube, which may be mounted across
the cavity to allow one or more additional layers to be injected
and formed around the elastic elements 750 and base material.
In addition to molding, other methods may be used for encasing or
otherwise incorporating elastic elements into base material to
provide an access device, such as those described elsewhere herein.
For example, one or more sheets, cylinders, or other configurations
of base material may be formed and elastic elements may be embedded
into and/or otherwise attached to the base material.
Turning to FIGS. 12A-12D, exemplary methods are shown for embedding
a set of elastic elements 850 into a sheet 832 of elastomeric or
other base material. For example, as shown in FIGS. 12A and 12B,
the elastic elements 850 may be formed and positioned in a desired
arrangement, e.g., with a plurality of individual or connected
zigzag elements disposed adjacent one another, e.g., in a relaxed
or pre-stressed state and/or nested or spaced apart, as shown in
FIG. 12A. A sheet 832 of base material may then be applied over the
elastic elements 850, as shown in FIG. 12B.
For example, a solid, cured sheet 832 of base material may be
applied and/or attached to the elastic elements 850. Optionally,
one or more additional layers of base material (not shown) may be
applied to the base material 832 over the elastic elements 850,
e.g., by bonding with adhesive, fusing, reflowing, and the like, to
encase the elastic elements 850 within the base material.
Alternatively, the elastic elements 850 may be placed within a tray
or other receptacle (not shown), and uncured or otherwise flowable
base material 832 may be poured over the elastic elements 850 into
the receptacle to encase the elastic elements 850 therein, e.g., as
shown in FIGS. 13A-13C and described further below, whereupon the
base material 832 may be cured, cross-linked, and/or otherwise
processed.
In a further alternative, as shown in FIGS. 12C and 12D, a sheet or
other substrate 832 of base material may be formed, and then a set
of elastic elements 850 may be placed within the substrate 832. For
example, as shown in FIGS. 13A-13C, base material may be mixed or
otherwise prepared such that the base material remains at least
partially uncured, e.g., such that the base material remains in a
liquid, gel, or other flowable state (not shown). A tray or other
receptacle 810 may be provided that includes a recess or depression
812 therein into which the flowable base material 832 may be
poured, as shown in FIG. 13B. Any excess base material 832 may be
removed, e.g., using a blade or other tool 820 that is directed
along a top surface 814 of the receptacle 810 to provide a
substantially planar exposed surface for the base material 832.
Once the excess material is removed, the elastic elements 850 may
then be inserted into the base material, as shown in FIG. 12D,
e.g., in a relaxed or pre-stressed state, similar to other
embodiments herein. The base material 832 may then be cured,
cross-linked, and/or other processed, e.g., to encase the elastic
elements 850 within the fully cured base material 832.
Alternatively, the base material 832 may be fully cured and then
the elastic elements 850 may placed on the base material 832 or
inserted into the base material 832, e.g., forced into, heated to
melt or reflow the base material 832 around the elastic elements
850, and the like. Alternatively, a "negative pattern" may be
created in the exposed surface of the base material 832, e.g.,
using a stamp or other tool (not shown) inserted into the exposed
surface of the uncured base material 832. The base material may
then be cured, cross-linked, and/or otherwise processed and the
tool removed to create a set of recesses corresponding to the
configuration of the struts of the elastic elements 850. Thus, the
elastic elements 850 may be received in the preformed recesses
rather than forced directly into the base material 832. Optionally,
one or more additional layers of base material (not shown) may be
applied over and/or otherwise fused or attached to the base
material 832, thereby encasing the elastic elements 850.
In yet another alternative, a spray/thin film deposition method may
be used to form the base material. For example, one or more layers
of elastomeric material may be sprayed in a liquid or powder form,
e.g., within a tray or other receptacle (not shown). Exemplary
spraying methods may include aerosol sprays, electrostatic charge
deposition (e.g., powder coating, copier ink/toner application),
ink jet deposition technology, and the like. After application of
the elastomeric material, additional steps may be taken to cure,
cross-link, and/or otherwise process the base material (e.g., by
applying one or more of heat, humidity, visible or ultraviolet
light, and the like). In one embodiment, elastomeric material may
be deposited over a die stamp, which creates an impression of the
configuration of the elastic elements 850 in its lower surface (not
shown). When the stamp is removed, the resulting base material 832
may include a recess pattern corresponding to the configuration of
the elastic elements 850. This may eliminate any need for
additional fixturing to position the elastic elements 850 since
they may nest into the recess pattern, which may also improve
device-to-device consistency. For ink jet deposition methods, a
recess pattern for the elastic elements 850 may be created
directly, e.g., as the base material is deposited.
In addition, the recess pattern may be selected such that the
elastic elements 850 are stressed when inserted into the recesses.
For example, the recess pattern may include recesses corresponding
to each of the struts of the elastic elements 850, but the recesses
may be spaced apart from a relaxed state of the elastic elements
850. Thus, the recess pattern and the base material surrounding the
recesses may retain the elastic elements 850 in a pre-stressed
state without requiring additional fixturing. Optionally, in these
methods, after the elastic elements 850 have been positioned in the
recess pattern, a final layer of base material may be applied to
completely embed or otherwise encase the elastic elements 850.
In still another alternative, a dip method may be used to create
the base material. For example, one or more layers of elastomeric
material may be applied over a mandrel (not shown), e.g., by
dipping the mandrel one or more times into the elastomeric
material, e.g., in a liquid form. The thickness of the resulting
base material may be controlled by one or more of the viscosity of
the liquid elastomer, percent solids content of the elastomer,
and/or number of dip applications. Another method to control the
thickness is to dip a pair of parallel plates into the liquid
solution, e.g., thereby forming a layer of base material between
the plates that has a thickness corresponding to the spacing of the
plates.
Turning to FIGS. 14A-14C, another method is shown for making an
elastic member or panel 1030 for an access device by thermally
welding a plurality of sheets or layers of base material 1030
around a set of elastic elements 1050. For example, as shown in
FIG. 14A, a pair of sheets 1010 of elastomeric material may be
provided, e.g., formed from any of the methods described elsewhere
herein, either with or without recess patterns (not shown)
corresponding to the elastic elements 1050.
The elastic elements 1050 may be positioned between the sheets
1010, and one or more of energy, pressure, and the like may be
applied to weld the two sheets 1010 together and/or embed the
elastic elements 1050 into the sheets 1010, e.g., resulting in the
assembly 1028 shown in FIG. 14A. Energy may be applied directly,
e.g., using heating elements (not shown), and/or indirectly, e.g.,
using one or more of radiofrequency (RF) electrical energy,
ultrasonic vibration, and friction, e.g., to concentrate the energy
at the interface between the sheets 1010. For example, the material
of the elastic elements 1050 may act as an energy director that
concentrates the resultant thermal energy at the inner surfaces of
the sheets 1010 to promote embedding the elastic elements 1050 into
and/or between the sheets 1010.
Optionally, as shown in FIG. 14B, a die 1020 may be used to apply
the energy and/or form the assembly 1028 into a finished elastic
sheet 1030 that may be incorporated into an access device (not
shown). As shown, the die 1020 may include opposing plates 1022,
1024 that may include one or more heating elements and/or sources
of other energy (not shown). For example, the upper plate 1022 may
include a heating element (not shown), or may be configured as a
cathode for RF welding and the lower plate 1024 may be configured
as an anode for RF welding.
The components of the assembly 1028 may be positioned between the
plates 1022, 1024, e.g., placing in sequence a first layer of base
material 1010, the elastic elements 1050 (relaxed or pre-stressed),
and a second layer of base material 1010 (shown in FIG. 14A) on the
lower plate 1024, and the plates 1022, 2024 may then be directed
together to apply pressure and/or other energy to the base material
1010 to attach them together, as described elsewhere herein.
Optionally, the plates 1022, 1024 may include one or more blades or
other cutting elements 1026 and opposing recesses 1027 arranged on
respective the plates 1022, 1024 to cut the assembly 1028 into the
final elastic panel 1030, e.g., as shown in FIG. 14C. The cutting
element(s) 1026 may be fixed or may be mechanically actuated, e.g.,
using one or more springs, pneumatics, hydraulics, and the like
(not shown) to press the cutting element(s) 1026 into and through
the assembly 1028 (e.g., to enhance cutting through the base
material 1032 and elastic elements 1050) into the opposing
recess(es) 1027.
Turning to FIGS. 15A-15D, another method is shown for making an
access device using a mandrel 1110, as shown in FIG. 15A, which may
define the inner diameter of the resulting access device. The
mandrel 1110 may be a solid or hollow cylindrical body formed from
materials able to withstand the processing used and/or to provide a
desired outer surface finish. Initially, as shown in FIG. 15B, a
first layer of elastomeric or other base material 1032 may be
provided around the mandrel 1110, e.g., by creating a first layer
of base material directly on the mandrel 1110, or by wrapping a
sheet of base material around the mandrel 1110, as shown in FIG.
15B. For example, the mandrel 1110 may be dipped in uncured, liquid
base material, similar to other embodiments herein, with the
thickness of the resulting coating controlled by one or more of
viscosity of the liquid elastomer, percent solids content, and
number of dip applications. Uniformity of application may also be
enhanced by positioning the mandrel 1110 substantially horizontally
after dipping and rotating the mandrel 1110 during curing.
Alternatively, as shown in FIG. 16, a first layer of base material
1132 may be applied around the mandrel 1110 while rotating the
mandrel 1110 and using a blade or other tool 1112 to remove excess
base material. For example, uncured, liquid base material may be
applied to the outer surface of the mandrel 1110 as it rotates,
e.g., by spraying, brushing, and the like, and the tool 1112 may
remove excess material such that the first layer 1132 achieves a
desired outer diameter. Optionally, the material may cure as the
mandrel 1110 is rotated, e.g., substantially continuously applying
and curing the base material, e.g., by applying heat or other
parameters to initiate curing as the base material is applied,
until the desired outer diameter is achieved.
In another alternative, base material (e.g., thermoset or
thermoplastic material) may be extruded through a die (not shown)
over the mandrel 1110 directly, or may be extruded over beading or
other subassembly (not shown) before being transferred to the
mandrel 1110.
In still another alternative, a cylinder may be formed over the
mandrel 1110 by wrapping a thin sheet or layer of flat base
material with attached elastic elements (not shown, e.g., formed
similar to other embodiments herein, such as the methods shown in
FIGS. 12-13) around the mandrel 1110, and attaching the ends of the
sheet together, e.g., by bonding with adhesive, fusing, mechanical
connectors, sutures (not shown), and the like.
Once the base material 1132 is formed and/or secured on the mandrel
1110, a set of elastic elements 1150 may be positioned around the
first layer 1132 or placed into the surface of the first layer 1132
if not already applied. For example, a recess pattern may be formed
in the outer surface of the first layer 1132, e.g., by laser
cutting, mechanical cutting, heating a stamp with the pattern (not
shown), and the like into the outer surface. Alternatively, the
elastic elements 1150 may be forced, heated, and/or otherwise
directed into the outer surface, as shown in FIG. 15C.
Finally, a second layer of base material 1134 may be applied around
the elastic elements 1150, e.g., by again creating the second layer
1134 directly on the mandrel 1110 (e.g., by dipping and curing,
spraying and curing, and the like) or wrapping a sheet of base
material around the mandrel 1110. For example, the second layer
1134 may be applied using the spray-on method shown in FIG. 16,
forming and rolling a layer of base material, and the like to
encase the elastic elements 1150.
Optionally, the resulting assembly may be processed further, e.g.,
to further cure or cross-link the base material, heat or fuse the
layers, and the like. The mandrel 1110 may then be removed and the
assembly incorporated into an access device, such as that shown in
FIGS. 2A-2C. Optionally, additional base material may be added,
e.g., using any combination of the other methods described herein,
to reinforce the cylindrical shape after the mandrel 1110 is
removed.
Turning to FIGS. 17A-17C, another method is shown for forming a
sheet of elastic material 1230, e.g., including a plurality of
elastic elements 1250 embedded in base material 1232. FIGS. 17A and
17B show front and end views of a sheet or layer of elastomeric
material, similar to any of the other embodiments herein. A
plurality of elastic elements 1250, e.g., individual curvilinear
wires or other filaments, may be threaded from one edge of the
sheet 1232 into and through the elastomeric material, as shown in
FIG. 17B, to the opposite edge, e.g., as shown in FIG. 17C.
Alternatively, a plurality of tubular guides, e.g., having straight
or curvilinear shapes (not shown) may be placed through the sheet
1232 from one edge to the opposite edge, and the filaments 1250 may
be threaded through the guides, which may then be removed. In this
alternative, the filaments 1250 may have a different relaxed shape
than the guides, such that the filaments 1250 become pre-stressed
within the elastomeric sheet 1232 once the guides are removed.
Exemplary embodiments of the present invention are described above.
Those skilled in the art will recognize that many embodiments are
possible within the scope of the invention. Other variations,
modifications, and combinations of the various components and
methods described herein can certainly be made and still fall
within the scope of the invention. For example, any of the devices
described herein may be combined with any of the delivery systems
and methods also described herein.
While embodiments of the present invention have been shown and
described, various modifications may be made without departing from
the scope of the present invention. The invention, therefore,
should not be limited, except to the following claims, and their
equivalents.
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